1.4 Domain 0.0.127.in-addr.arpa

The IP address 127.0.0.1 presents an interesting complication. Network 127 is reserved for loopback, i.e., a software loop on each computer. While other IP addresses are unambiguous within the Internet, the address 127.0.0.1 occurs on every computer. Each name server is not only an authority for common domains, but also an authority (primary name server) to domain 0.0.127.in-addr.arpa. We will consider this as given and will not list it in the chart, but be careful not to forget about it. For example, even a caching-only server is a primary server for this domain. Windows 2000 pretends to be the only exception to this rule, but it would not hurt for even Windows 2000 to establish a name server for zone 0.0.127.in-addr.arpa.